When high school student Kim Eun-mi discovered that she was pregnant, her entire life changed in an instant. Determined to keep her baby, Eun-mi did just that. Raising her daughter, Jin-hee on her own, the two have quite literally grown up together. — Now in her forties, Eun-mi works as a physical therapist while 29-year-old Jin-hee works as an officer at the Namchon Police Substation. Despite being an adult herself, Jin-hee still lives with her mother; a fact which leads to an endless stream of bickering between the two. — As if struggling to find a way to deal with her daughter wasn’t enough, Eun-mi’s life takes a complicated turn when Dr. Park Jin-hong suddenly appears before her. While Eun-mi tries to make sense of the mysterious Dr. Park, Jin-hee struggles to find a way to get along with her work’s new director, Eun Jae-won. With life taking one complicated turn after another, will mother and daughter ever find a way to repair the breach that’s been widening between them?